try rebooting the device and adding the account again. Also if that doesn't help use mobile data to add it.
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varunyellinaNov 19 '12 at 15:06

I tried many times. Eventually it worked. Unfortunately I don't really understand why. What was also irritating was that when I succeeded it insisted on starting to sync contacts/mail/calendar, so I had to turn those off manually as fast as I could
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Klas MellbournNov 20 '12 at 7:49